

What is ULTRANOX™ 626?
ULTRANOX™ 626 is a high-performance organophosphite antioxidant that is specially designed for demanding applications where color stability is required. ULTRANOX™ 626 is a secondary antioxidant with one of the market's highest phosphorous content, providing improved protection, reduced loading rate, and lower overall cost.It is one of the highest phosphorous content secondary antioxidants in the market, which provides improved protection, reduced loading rate, and lower overall cost. This phosphite antioxidant is available in powder and granular form and supplied by SI Group, a lead in polymer additives and stabilizers.
ULTRANOX™ 626 is also featured with FDA food contact approval for conditions A through H for use in polypropylene (PP) polymers and copolymers. The FDA approval, combined with performance benefits make ULTRANOX® 626 ideal for use in a wide range of polypropylene packaging and many other food contact applications.
Bis(2,4-di-tert-butylphenyl)-pentaerythritol diphosphate
CAS No. 26741-53-7
Why Should You Use ULTRANOX™ 626 Additive?
- Higher phosphorous content than competitive phosphite antioxidants
- Exceptional color, melt stability, and protection
- Excellent synergy with phenolic antioxidants
- Exhibits low-gas-fading characteristics for critical fiber and film applications
- Very effective in mineral-filled and black-filled PP processing
- Cost-efficient due to its high active content and low level of use
- Top quality, produced domestically in WV
- Capable of excellent synergy with benzophenones and benzotriazoles light stabilizers
- Supply security, dedicated production line for ULTRANOX™ 626
- Broad range of A–H FDA compliance
ULTRANOX™ 626 In Packaging Applications
ULTRANOX™ 626 is an excellent antioxidant for food packaging producers and brand owners due to its FDA compliance, advanced color stability, and lower cost (lower loading rate). It provides the quality, reliability, and cost savings required in the modern, fast-growing packaging market.








ULTRANOX™ 626 Features & Benefits By Resin Type:
- FDA approved under the conditions of use A–H as listed in FCN 1988
- Color stability and melt flow retention
- Low interaction and low gas fading with peroxides
- Excellent synergy with ALKANOX™ 240 phosphite antioxidant
- Typical use level: ULTRANOX™ 626 at 0.08% - 0.12% + ANOX™ IC-14 at 0.04% - 0.06%
- Proven results with reduced loading rate and lower overall cost
- Less film breakage allows increased machine up-time andproductivity
- Faster line speeds enabling more cost-efficient operations
- Crystal clear films for higher brand value
- Excellent synergy with ANOX™ IC-14 stabilizer
- Typical use level: ULTRANOX™ 626 at 0.04% – 0.08% + ANOX™ IC-14 at 0.02% - 0.04%
- Proven results with reduced loading rate and lower overall cost
Polypropylene Resins
BOPP Resins
- Excellent control of the PET molecular weight during severe processing
- High activity color and MFI protection
- Prevents PET discoloration during heat aging
- ULTRANOX™ 627AV is used when PET contains Sb2O3 catalyst
- Molecular weight control for high melt strength
- Allowing high regrind usage without discoloration
- Excellent color and melt flow retention
- Typical use level: ULTRANOX™ 626 at 0.08 – 0.1% + ANOX™ IC-14 at 0.04 - 0.1%
PET Resins
Thermoforming Resins
Summary
ULTRANOX™ 626 is a high-performance antioxidant that improves performance for packaging and food contact plastic manufacturers. This organophosphite antioxidant offers efficiency benefits for a wide array of polymer systems. Talk to an expert today about how ULTRANOX™ 626 can work for your formulation.
